Avoid using PHPUnit_Framework_MockObject_MockObject

[lbajsarowicz]

Rule

PHPUnit_Framework_MockObject_MockObject triggers warning

Reason

The PHPUnit_Framework_MockObject_MockObject was deprecated long time ago and \PHPUnit\Framework\MockObject\MockObject should be used

Implementation

[ihor-sviziev]

As for now I added this class to dev/tests/static/testsuite/Magento/Test/Legacy/_files/obsolete_classes.php as part of magento/magento2#27519

I don't really think is's good idea to have such check in magento coding standards.

[lenaorobei]

@lbajsarowicz agree with @ihor-sviziev.
I'm closing this issue in favor of internal task MC-33003 for implementing regular static test but not the part of coding standard.

[lbajsarowicz]

Thank you.